A Highly Sensitive and Selective Sb‐Doped MoS 2 Monolayer in Detecting Toxic Gases: Insight From DFT and NEGF

ABSTRACT In this work, the adsorption properties and sensitivity of Sb‐doped MoS 2 for the selective detection of various environmental toxic gases (CO, CO 2 , NO, NO 2 , SO 2 , and SO 3 ) were investigated using Density Functional Theory combined with the Nonequilibrium Green's Function formalism. The Perdew–Burke–Ernzerhof functional within the Generalized Gradient Approximation was employed for the computational analysis. Key parameters such as adsorption energy, charge transfer, bandgap, Density of States, Projected Density of States, optical properties, work function, recovery time, current–voltage characteristics, and sensitivity were examined to understand the adsorption behavior of the Sb–MoS 2 monolayer toward these gases. The results indicate strong adsorption energies for SO 3 and NO 2 , with values of −1.71 and −1.50 eV, respectively. SO 3 , NO, NO 2 , and CO exhibit chemisorption, whereas SO 2 and CO 2 undergo physisorption. The optical analysis reveals noticeable changes in the absorption and reflection of incident photon energy upon gas adsorption. Among all gases, CO shows the highest sensitivity of 68.32% at a bias voltage of 1.7 V, while NO exhibits the lowest sensitivity of 21.86% at 1.8 V. This study lays the groundwork for the development of Sb–MoS 2 monolayers as highly sensitive FET‐based sensors for the detection and monitoring of environmental toxic gases.